反应详情

To 10 ml of ethanol was added 1.1 g of the 1-(3-benzyl-1,5-dihydro-5-thioxo-4H-1,2,4-triazol-4-yl)-2-propanone ethylenacetal obtained in Reference Example 5, followed by addition of 5.0 ml of 2N-hydrochloric acid. The mixture was refluxed for 40 minutes and, then, concentrated to half the original volume. To the concentrate was added water and the resultant precipitate was recovered by filtration. This procedure provided 1-(3-benzyl-1,5-dihydro-5-thioxo-4H-1,2,4-triazol-4-yl)-2-propanone as crystals. Recrystallization from ethyl acetate gave colorless needles melting at 163°-165° C.

1. customobtained in Reference Example 5
2. temperatureThe mixture was refluxed for 40 minutes
3. concentrationconcentrated to half the original volume
4. additionTo the concentrate was added water
5. filtrationthe resultant precipitate was recovered by filtration